Dispersion occurs in the characteristics of the transistors. The invention
is a signal line driving circuit having a first and a second current
source circuits corresponding to each of a plurality of signal lines, a
shift register, and a constant current source for video signal, in which
the first current source circuit is disposed in a first latch and the
second current source circuit is disposed in a second latch. The first
current source circuit includes capacitive means for converting the
current supplied from the constant current source for video signal into a
voltage, according to a sampling pulse supplied from the shift register,
and supplying means for supplying the current corresponding to the
converted voltage. The second current source circuit includes capacitive
means for converting the current supplied from the first latch into a
voltage, according to a latch pulse, and supplying means for supplying
the current corresponding to the converted voltage.